Accumulated Other Comprehensive Income (Loss) - Reclassifications Out of Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses	$ 244,672	$ 233,773	$ 717,648	$ 678,647
Tax (benefit) expense	19,431	20,815	44,414	48,929
Total reclassifications for the period, net of tax	(28,397)	(30,536)	(66,036)	(70,993)
Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses	4,836	4,420	14,508	13,259
Tax (benefit) expense	(1,881)	(1,719)	(5,644)	(5,158)
Total reclassifications for the period, net of tax	2,955	2,701	8,864	8,101
Actuarial Losses Recognized | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses	5,268	4,727	15,804	14,180
Tax (benefit) expense	(2,049)	(1,839)	(6,148)	(5,517)
Total reclassifications for the period, net of tax	3,219	2,888	9,656	8,663
Prior Service Costs Recognized | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Selling, general and administrative expenses	(432)	(307)	(1,296)	(921)
Tax (benefit) expense	168	120	504	359
Total reclassifications for the period, net of tax	$ (264)	$ (187)	$ (792)	$ (562)